A percutaneous implant is an object, foreign to the body, that has been placed through the skin to allow a port of entry to inner body spaces and structures. Temporary percutaneous access is required for a wide variety of procedures such as intra-venous fluid administration and hemodialysis. A number of these procedures also require chronic access. Specific examples of applications which benefit from a chronic percutaneous port include hemodialysis access, peritoneal dialysis access, power supply leads and fluid connections for artificial organs, charging for cardiac pacemakers, neuroelectric stimulation of nerves and/or muscles, artificial stimulation and monitoring in various brain implants.
Acute percutaneous access is routinely accomplished with devices constructed of silicone, polypropylene and polyurethane. These devices serve as a mechanism by which to gain blood access, wound drainage and many other applications. The chronic use of such devices, however, commonly results in infection and/or encapsulation of the device by the epidermis. Past attempts to overcome these problems have included a variety of devices constructed of various materials and have included both rigid and flexible devices.
Percutaneous implant devices are designed to prevent bacteria from entering the body through skin exit site areas. The standard design for percutaneous implants consists of a central conduit surrounded by an attached flange. The flange can be a rigid or flexible disk that is covered with a flexible biocompatible material such as expanded polytetrafluoroethylene (PTFE), polyester and polyamide velours, polyurethane, polypropylene and polyethylene. These biocompatible materials are normally porous in structure to allow for sufficient connective tissue ingrowth and anchorage. Epithelium is directed downward allowing for contact epithelium inhibition and forms a bacterial seal with connective tissue preventing the evagination and extrusion of the percutaneous implant device. Connective tissue ingrowth and vascularization are designed to form a barrier at the skin exit site to prevent foreign material and microorganisms from entering the body.
There is a need for an easily handled and effective system for preventing foreign material and microorganisms from entering through the lumen, a major problem when the exchange of fluids into or out of the body is required. Most percutaneous implants contain a central conduit of a biocompatible material that is attached to the flange ingrowth segment of the device. The common conduit materials are polydimethylsiloxane (silcone rubber), polyurethane, polyethylene, polypropylene, polytetrafluoroethylene, polycarbonate, titanium and carbon. This conduit extends through the body and is capped by a variety of means. When filling the conduit with materials such as wires, fibers and various leads, contamination is not a great problem because these materials can be sealed or adhered solidly into the lumen of the conduit. This solid barrier in the lumen allows for a variety of attachment mechanisms such as magnets, screw on devices and friction fit apparatus to be utilized as connection and disconnection systems. Because these conduits are not open conduits, special connectors that act as a mechanical fuse and separate at the interface without damage to the interface have been developed as set forth in U.S. Pat. No. 4,004,298.
Openings through the flange ingrowth segment are provided to allow for the passage of a variety of tubings, catheters and conduits. These conduits are permanently attached to the flange portion by molding, sealing or adhesion or they can be temporarily placed through the flange portion as shown in U.S. Pat. No. 3,402,710. Through the lumen of these various conduits, fluids are allowed to flow in and out of the body. At the exterior, proximal end of these conduits, outside the body, standard luer lock fittings and adapters can be secured. The potential for an exposed lumen in the conduit can occur anytime a connection or disconnection is made with an additional fluid line, such as an intravenous line. Any breaks or holes in any part of the system also lead to an exposed lumen. Any time the conduit is opened in any manner, the introduction of infection may result, leading to septicemea, emboli, backbleeding or backflow of other vital body fluids (Coppa, G. F., Gouge, T. H., and Hofstetter, S. R.: Air Embolism: A Lethal but Preventable Complication of Subclavian Vein Catheterization. J. Parenteral & Enternal Nutrition 5(2):166-168, Mar/Apr 1981).
Skin interface disruption can also result when conduits protrude from the body. The forces disrupting the interface are normally caused by actions such as twisting, tugging and pulling while handling the external portion of the conduit during connection and disconnection (Von Recum, A. F., and Park, J. B.: Permanent Percutaneous Devices. CPC Critical Reviews in Bioengineering 5(1):37-77, 1981). Without proper dressings and taping of the conduit down to the skin, tightness of clothing can also irritate the interface site presenting additional trauma (Erlich, L. F., and Powell, S. L.: Care of the patient with a Gore-Tex Peritoneal Dialysis Catheter. Dialysis & Transplantation 12(8):572-577, Aug. 1983).
Because of the need to physically seal an open conduit during connections and disconnections, mechanical damage can result, necessitating repairs or the eventual removal of the device. The same type of damage that occurs to standard catheters can occur to any type of conduit placed through a percutaneous device because of the necessity to physically seal the lumen during connections and disconnections (Gulley, R. M., Hawk, N.: Rupture of Indwelling Venous Catheters. J Parenteral & Enteral Nutrition 7(2):184-185, Mar/Apr, 1983).
Prior art has disclosed a percutaneous implant device for drug injection with a normally closed value in a passageway, for administration of medication, e.g. U.S. Pat. No. 3,783,868 and 4,321,914. However, the known prior art does not address the complications of skin exit disruptions due to forces applied to the exterior portions of the conduit during connections and disconnections.
The solution to these problems is found in the improved implant device of this invention that utilizes design advantages, the physical properties of the materials used and a unique handling system.